[meteorite-list] Has China's Ailing Moon Rover Survived 2nd Lunar Night?

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 12 Feb 2014 16:27:50 -0800 (PST)
Message-ID: <201402130027.s1D0RoRd021946_at_zagami.jpl.nasa.gov>

http://www.space.com/24665-china-moon-rover-lunar-night-survival.html

Has China's Ailing Moon Rover Survived 2nd Lunar Night?
By Leonard David,
space.com
February 12, 2014

China's first moon lander, Chang'e 3, is reportedly up and running following
its second encounter with the vicious lunar night cycle. But whether the
lander's sidekick, the Yutu moon rover, also survived the lunar cold is
not immediately clear.

The stationary Chang'e 3 lunar lander appears to have emerged from its
second hibernation period following the 14-day lunar night. The reportedly
now active lander went into a controlled hibernation mode on Jan. 24 Beijing
Time.

Meanwhile, the mobile Yutu rover - meaning "Jade Rabbit" - may well have
frozen to death. China's space agency has yet to release an official status
update on the rover. The state-run China Daily newspaper reported that,
as of Monday, the rover "could not be restored to full function" and that
fans of the mission were mourning the development on Weibo, China's Twitter
equivalent.

Chang'e 3 landed on the moon's Mare Imbrium (Sea of Rains) on Dec. 14.
Shortly after landing, the small rover was deployed and began its patrol
of the crater-pocked surface.

"Despite the seemingly premature demise of the Yutu rover, the Chinese
have accomplished all of their major mission objectives," said Paul Spudis,
a planetary geology and remote sensing expert at the Lunar and Planetary
Institute in Houston.

"They have developed a lander spacecraft that can safely place payloads
on the lunar surface - this ability translates into the ability to encounter
and conduct proximity operations around any object in cislunar space,"
Spudis told Space.com. "The Chang'e 3 mission is a major advance in their
spacefaring capabilities."

Control anomaly

China's robotic Chang'e 3 lander and Yutu moon rover draw power from their
respective solar arrays, but also have plutonium-powered batteries to
keep warm their innards of electronic components.

Chinese engineers at the Beijing Institute of Spacecraft System Engineering
have previously noted that creative techniques in thermal control technology
for the Chang'e 3 moon mission were called for, such as radioisotope heat,
gravity-assisted fluid loops, heat pipes and other thermal control hardware
and insulation.

Whether the Yutu rover, which weighs 308 lbs. (140 kilograms), has come
out of its 'cosmic coma" remains unknown. Prior to the onset of the lengthy
lunar night, the Chinese moon rover experienced a mechanical control anomaly
that may have spelled its doom.

The rover abnormality occurred due to "complicated lunar surface environment,"
the State Administration of Science, Technology and Industry for National
Defense (SASTIND) reported Jan. 25.

Bite the lunar dust?

What specifically happened to Yutu is not known, but the pervasive lunar
dust is speculated to have possibly gummed up mechanisms on the rover.

According to Philip Stooke, associate professor in the Department of Geography
at the University of Western Ontario in Canada, Yutu's camera mast, also
carrying a high gain antenna, were supposed to fold down into a box on
the rover body, and then be covered by one of the panels.

'That enclosed space is kept warm by a radioactive heat source. The second
solar panel is tilted down and oriented to catch the rays of the rising
sun," Stooke told Space.com. It appears that the first panel would not
close, he speculated, with the expectation that the cameras would then
be damaged by the cold and maybe other items in need of warmth too.

Prior to Yutu's launch toward the moon, Chinese space officials said the
rover was projected to carry out tasks for three months. It totes nearly
45 lbs. (20 kg) of scientific instruments.

The rover successfully used its panoramic and navigational cameras, an
arm tipped with an Alpha-Proton X-ray Spectrometer and a radar system
attached to its underbelly to reconnoiter the moon's subsurface.

The stationary lander is built to work for a year and has already made
use of an extreme ultraviolet camera to observe the Earth's plasmasphere,
as well as an optical telescope to view other celestial objects from the
lunar surface.

When word came last month that Yutu might not endure its deep freeze,
thousands of Chinese "netizens" posted their blessings to the robot.

As reported by the state-run Xinhua news agency, China's social networking
circles were abuzz with farewells to the robot.

"You have done a great job Yutu. You have endured extreme hot and cold
temperatures and shown us what we have never seen," wrote one Yutu supporter
under the name "Amaniandlove," according to Xinhua. Hope you get well
soon, but no matter what, it is your presence that makes the planet about
390 thousand kilometers away dazzling."
Received on Wed 12 Feb 2014 07:27:50 PM PST